Eur J Endocrinol 2004;150:525-32
Mohlig M, Spranger J, Osterhoff M et al.
The syndrome of polycystic ovaries (PCOS) is a known risk factor for type 2 diabetes. It is not known, however, whether the increase in diabetes risk is related to hormone abnormalities associated with PCOS such as increased testosterone, or whether it is a result of the excess weight frequently observed in PCOS women.
The level of certain substances in the blood (called interleukin-6 or IL-6 and C-reactive protein or CRP) is supposed to predict type 2 diabetes. However, these substances are also found in obesity without PCOS. Scientists at the German institute of Human Nutrition measured the blood levels of IL-6 and CRP, in combination with measures of obesity, insulin resistance and testosterone in 57 women with PCOS and in 20 healthy women in a similar age group.
Neither CRP nor IL-6 were significantly elevated in lean or obese PCOS women compared with age-matched lean or obese controls. In PCOS patients, the body mass index (BMI), waist to hip ratio, fat mass and insulin resistance were correlated with IL-6 or CRP. Further analysis revealed that obesity is the dominant force, thus explaining 18% and 24% of the IL-6 or CRP levels, respectively, in PCOS women.
Nine of the obese, insulin-resistant PCOS patients were then treated with Metformin (a diabetes medication) over a period of 6 months and this caused a significant decrease in body weight, body fat mass and total testosterone, but showed no significant decline in IL-6 or CRP concentrations.
The authors concluded that in PCOS women, BMI was most strongly related to IL-6 and CRP in PCOS; thus PCOS-related hormone abnormalities (such as raised testosterone) do not appear to activate IL-6 and CRP but instead obesity is the main cause of type 2 diabetes in patients with this condition. Treatment of obesity, could prevent the onset of diabetes.
